Tomato line psq 176-09pw0002

ABSTRACT

The invention provides seed and plants of the tomato line designated PSQ 176-09PW0002. The invention thus relates to the plants, seeds and tissue cultures of tomato line PSQ 176-09PW0002, and to methods for producing a tomato plant produced by crossing a plant of tomato line PSQ 176-09PW0002 with itself or with another tomato plant, such as a plant of another line. The invention further relates to seeds and plants produced by such crossing. The invention further relates to parts of a plant of tomato line PSQ 176-09PW0002, including the seed, pod, and gametes of such plants.

FIELD OF THE INVENTION

The present invention relates to the field of plant breeding and, more specifically, to the development of tomato line PSQ 176-09PW0002.

BACKGROUND OF THE INVENTION

The goal of vegetable breeding is to combine various desirable traits in a single variety/hybrid. Such desirable traits may include greater yield, resistance to insects or pests, tolerance to heat and drought, better agronomic quality, higher nutritional value, growth rate and fruit or pod properties.

Breeding techniques take advantage of a plant's method of pollination. There are two general methods of pollination: a plant self-pollinates if pollen from one flower is transferred to the same or another flower of the same plant or plant variety. A plant cross-pollinates if pollen comes to it from a flower of a different plant variety.

Plants that have been self-pollinated and selected for type over many generations become homozygous at almost all gene loci and produce a uniform population of true breeding progeny, a homozygous plant. A cross between two such homozygous plants of different varieties produces a uniform population of hybrid plants that are heterozygous for many gene loci. Conversely, a cross of two plants each heterozygous at a number of loci produces a population of hybrid plants that differ genetically and are not uniform. The resulting non-uniformity makes performance unpredictable.

The development of uniform varieties requires the development of homozygous inbred plants, the crossing of these inbred plants, and the evaluation of the crosses. Pedigree breeding and recurrent selection are examples of breeding methods that have been used to develop inbred plants from breeding populations. Those breeding methods combine the genetic backgrounds from two or more plants or various other broad-based sources into breeding pools from which new lines are developed by selfing and selection of desired phenotypes. The new lines are evaluated to determine which of those have commercial potential.

SUMMARY OF THE INVENTION

In one aspect, the present invention provides a tomato plant of the line designated PSQ 176-09PW0002. Also provided are tomato plants having all the physiological and morphological characteristics of the tomato line designated PSQ 176-09PW0002. Parts of the tomato plant of the present invention are also provided, for example, including pollen, an ovule, a scion, a rootstock, a fruit, and a cell of the plant.

The invention also concerns the seed of tomato line PSQ 176-09PW0002. The tomato seed of the invention may be provided as an essentially homogeneous population of tomato seed of the line designated PSQ 176-09PW0002. Essentially homogeneous populations of seed are generally free from substantial numbers of other seed. Therefore, seed of line PSQ 176-09PW0002 may be defined as forming at least about 97% of the total seed, including at least about 98%, 99% or more of the seed. The population of tomato seed may be particularly defined as being essentially free from hybrid seed. The seed population may be separately grown to provide an essentially homogeneous population of tomato plants designated PSQ 176-09PW0002.

In another aspect of the invention, a plant of tomato line PSQ 176-09PW0002 comprising an added heritable trait is provided. The heritable trait may comprise a genetic locus that is, for example, a dominant or recessive allele. In one embodiment of the invention, a plant of tomato line PSQ 176-09PW0002 is defined as comprising a single locus conversion. In specific embodiments of the invention, an added genetic locus confers one or more traits such as, for example, herbicide tolerance, insect resistance, disease resistance, and modified carbohydrate metabolism. In further embodiments, the trait may be conferred by a naturally occurring gene introduced into the genome of the line by backcrossing, a natural or induced mutation, or a transgene introduced through genetic transformation techniques into the plant or a progenitor of any previous generation thereof. When introduced through transformation, a genetic locus may comprise one or more genes integrated at a single chromosomal location.

In another aspect of the invention, a tissue culture of regenerable cells of a tomato plant of line PSQ 176-09PW0002 is provided. The tissue culture will preferably be capable of regenerating tomato plants capable of expressing all of the physiological and morphological characteristics of the line, and of regenerating plants having substantially the same genotype as other plants of the line. Examples of some of the physiological and morphological characteristics of the line PSQ 176-09PW0002 include those traits set forth in the tables herein. The regenerable cells in such tissue cultures may be derived, for example, from embryos, meristems, cotyledons, pollen, leaves, anthers, roots, root tips, pistil, flower, seed and stalks. Still further, the present invention provides tomato plants regenerated from a tissue culture of the invention, the plants having all the physiological and morphological characteristics of line PSQ 176-09PW0002.

In yet another aspect of the invention, processes are provided for producing tomato seeds, fruit, and plants, which processes generally comprise crossing a first parent tomato plant with a second parent tomato plant, wherein at least one of the first or second parent tomato plants is a plant of the line designated PSQ 176-09PW0002. These processes may be further exemplified as processes for preparing hybrid tomato seed or plants, wherein a first tomato plant is crossed with a second tomato plant of a different, distinct line to provide a hybrid that has, as one of its parents, the tomato plant line PSQ 176-09PW0002. In these processes, crossing will result in the production of seed. The seed production occurs regardless of whether the seed is collected or not.

In one embodiment of the invention, the first step in “crossing” comprises planting seeds of a first and second parent tomato plant, often in proximity so that pollination will occur for example, mediated by insect vectors. Alternatively, pollen can be transferred manually. Where the plant is self-pollinated, pollination may occur without the need for direct human intervention other than plant cultivation.

A second step may comprise cultivating or growing the seeds of first and second parent tomato plants into plants that bear flowers. A third step may comprise preventing self-pollination of the plants, such as by emasculating the flowers (i.e., killing or removing the pollen).

A fourth step for a hybrid cross may comprise cross-pollination between the first and second parent tomato plants. Yet another step comprises harvesting the seeds from at least one of the parent tomato plants. The harvested seed can be grown to produce a tomato plant or hybrid tomato plant.

The present invention also provides the tomato seeds and plants produced by a process that comprises crossing a first parent tomato plant with a second parent tomato plant, wherein at least one of the first or second parent tomato plants is a plant of the line designated PSQ 176-09PW0002. In one embodiment of the invention, tomato seed and plants produced by the process are first generation (F₁) hybrid tomato seed and plants produced by crossing a plant in accordance with the invention with another, distinct plant. The present invention further contemplates plant parts of such an F₁ hybrid tomato plant, and methods of use thereof. Therefore, certain exemplary embodiments of the invention provide an F₁ hybrid tomato plant and seed thereof.

In still yet another aspect, the present invention provides a method of producing a plant derived from line PSQ 176-09PW0002, the method comprising the steps of: (a) preparing a progeny plant derived from line PSQ 176-09PW0002, wherein said preparing comprises crossing a plant of the line PSQ 176-09PW0002 with a second plant; and (b) crossing the progeny plant with itself or a second plant to produce a seed of a progeny plant of a subsequent generation. In further embodiments, the method may additionally comprise: (c) growing a progeny plant of a subsequent generation from said seed of a progeny plant of a subsequent generation and crossing the progeny plant of a subsequent generation with itself or a second plant; and repeating the steps for an additional 3-10 generations to produce a plant derived from line PSQ 176-09PW0002. The plant derived from line PSQ 176-09PW0002 may be an inbred line, and the aforementioned repeated crossing steps may be defined as comprising sufficient inbreeding to produce the inbred line. In the method, it may be desirable to select particular plants resulting from step (c) for continued crossing according to steps (b) and (c). By selecting plants having one or more desirable traits, a plant derived from line PSQ 176-09PW0002 is obtained which possesses some of the desirable traits of the line as well as potentially other selected traits.

In certain embodiments, the present invention provides a method of producing food or feed comprising: (a) obtaining a plant of tomato line PSQ 176-09PW0002, wherein the plant has been cultivated to maturity, and (b) collecting at least one tomato from the plant.

In still yet another aspect of the invention, the genetic complement of the tomato plant line designated PSQ 176-09PW0002 is provided. The phrase “genetic complement” is used to refer to the aggregate of nucleotide sequences, the expression of which sequences defines the phenotype of, in the present case, a tomato plant, or a cell or tissue of that plant. A genetic complement thus represents the genetic makeup of a cell, tissue or plant, and a hybrid genetic complement represents the genetic make up of a hybrid cell, tissue or plant. The invention thus provides tomato plant cells that have a genetic complement in accordance with the tomato plant cells disclosed herein, and seeds and plants containing such cells.

Plant genetic complements may be assessed by genetic marker profiles, and by the expression of phenotypic traits that are characteristic of the expression of the genetic complement, e.g., isozyme typing profiles. It is understood that line PSQ 176-09PW0002 could be identified by any of the many well known techniques such as, for example, Simple Sequence Length Polymorphisms (SSLPs) (Williams et al., Nucleic Acids Res., 1 8:6531 6535, 1990), Randomly Amplified Polymorphic DNAs (RAPDs), DNA Amplification Fingerprinting (DAF), Sequence Characterized Amplified Regions (SCARs), Arbitrary Primed Polymerase Chain Reaction (AP-PCR), Amplified Fragment Length Polymorphisms (AFLPs) (EP 534 858, specifically incorporated herein by reference in its entirety), and Single Nucleotide Polymorphisms (SNPs) (Wang et al., Science, 280:1077-1082, 1998).

In still yet another aspect, the present invention provides hybrid genetic complements, as represented by tomato plant cells, tissues, plants, and seeds, formed by the combination of a haploid genetic complement of a tomato plant of the invention with a haploid genetic complement of a second tomato plant, preferably, another, distinct tomato plant. In another aspect, the present invention provides a tomato plant regenerated from a tissue culture that comprises a hybrid genetic complement of this invention.

Any embodiment discussed herein with respect to one aspect of the invention applies to other aspects of the invention as well, unless specifically noted.

The term “about” is used to indicate that a value includes the standard deviation of error for the device or method being employed to determine the value. The use of the term “or” in the claims is used to mean “and/or” unless explicitly indicated to refer to alternatives only or the alternatives are mutually exclusive, although the disclosure supports a definition that refers to only alternatives and to “and/or.” When used in conjunction with the word “comprising” or other open language in the claims, the words “a” and “an” denote “one or more,” unless specifically noted. The terms “comprise,” “have” and “include” are open-ended linking verbs. Any forms or tenses of one or more of these verbs, such as “comprises,” “comprising,” “has,” “having,” “includes” and “including,” are also open-ended. For example, any method that “comprises,” “has” or “includes” one or more steps is not limited to possessing only those one or more steps and also covers other unlisted steps. Similarly, any plant that “comprises,” “has” or “includes” one or more traits is not limited to possessing only those one or more traits and covers other unlisted traits.

Other objects, features and advantages of the present invention will become apparent from the following detailed description. It should be understood, however, that the detailed description and any specific examples provided, while indicating specific embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.

DETAILED DESCRIPTION OF THE INVENTION

The invention provides methods and compositions relating to plants, seeds and derivatives of tomato line PSQ 176-09PW0002. This line shows uniformity and stability within the limits of environmental influence for the traits described hereinafter. Tomato line PSQ 176-09PW0002 provides sufficient seed yield. By crossing with a distinct second plant, uniform F1 hybrid progeny can be obtained. The development of tomato line PSQ 176-09PW0002 can be summarized as follows.

A. Origin and Breeding History of Tomato Line PSQ 176-09PW0002

Line PSQ 176-09PW0002 is a semi-determinate plant, with poor setting and medium vigor. The line has low yield, square fruit shape, and high brix level.

PSQ 176-09PW0002 was developed at the AB-2 female breeding program, converting variety PSQ-176-LAW into a nematode resistance version.

The nematode resistance gene origin came from an old processing line followed by Mi-Rex marker. The source was crossed with the recurrent line PSQ-176-LAW (BR-1) up to back-cross #3. Within 3 generation the line was fixed for Nematode resistance in addition to the other genotypic and phenotypic traits of the recurrent line PSQ-176-LAW (BR-1). PSQ 176-09PW0002 was used not only in the “AB-2 breeding program” but in many other developmental crosses.

Breeding history (Breeding scheme), Year 1-Year 7;

Step 1—crossing the source with recurrent line.

Step 2—fixation and single plant selection from BC3 to BC3S4.

Step 3—fixation and single plant selection from BC3S4 to F7.

Step 4—finishing the line by single plant and bulk selection to F9.

PSQ 176-09PW0002 has been observed as uniform and stable within commercially acceptable limits. As is true with other tomato inbreds, a small percentage of variants can occur within commercially acceptable limits for almost any characteristic during the course of repeated multiplication. However, no known variants were observed during field trial observations or greenhouse crossing block observations.

B. Physiological and Morphological Characteristics of Tomato Line PSQ 176-09PW0002

In accordance with one aspect of the present invention, there is provided a plant having the physiological and morphological characteristics of tomato line PSQ 176-09PW0002. A description of the physiological and morphological characteristics of tomato line PSQ 176-09PW0002 is presented in Table 1.

TABLE 1 Physiological and Morphological Characteristics of Line PSQ 176-09PW0002 Comparison: Characteristic PSQ 176-09PW0002 PSQ-176-LAW 1. Seedling anthocyanin in hypocotyl of 2-15 cm present present seedling (Montfavet H 63.4) habit of 3-4 week old seedling normal normal 2. Mature Plant height 62.6 cm 66.7 cm growth type determinate determinate (Campbell 1327, Prisca) plant: number of inflorescences on few (Campbell 1327) medium main stem (side shoots to be removed) form normal normal size of canopy (compared to others of medium medium similar type) habit semi-erect semi-erect 3. Stem anthocyanin coloration of upper third absent or very weak absent or very weak branching intermediate intermediate (Westover) branching at cotyledon or first leafy present present node number of nodes between first 7 to 10 1 to 4 inflorescence number of nodes between early (1^(st) to 1 to 4 4 to 7 2^(nd), 2^(nd) to 3^(rd)) inflorescences number of nodes between later 4 to 7 1 to 4 developing inflorescences pubescence on younger stems smooth (no long smooth hairs) 4. Leaf type (mature leaf beneath the 3^(rd) tomato tomato inflorescence) morphology (mature leaf beneath the leaflets are petiolate, leaflets are petiolate, 3^(rd) inflorescence) irregular lobed with irregular lobed with tooth edges tooth edges margins of major leaflets (mature leaf shallowly toothed or shallowly toothed or beneath the 3^(rd) inflorescence) scalloped scalloped marginal rolling or wiltiness (mature slight absent leaf beneath the 3^(rd) inflorescence) onset of leaflet rolling early season surface of major leaflets (mature leaf smooth smooth beneath the 3^(rd) inflorescence) pubescence (mature leaf beneath the smooth (no long smooth 3^(rd) inflorescence) hairs) attitude (in middle third of plant) horizontal (Aromata, semi-erect Triton) length medium (Lorena) medium width medium narrow division of blade pinnate (Mikado, pinnate Pilot, Red Jacket) size of leaflets (in middle of leaf) medium medium (Marmande VR, Royesta) intensity of green color dark (Allround, medium Daniela, Lorena, Red Robin) glossiness (as for 6) weak (Daniela) medium blistering (as for 6) weak (Daniela) weak size of blisters (as for 6) medium small (Marmande VR) attitude of petiole of leaflet in relation semi-erect (Blizzard, horizontal to main axis (in middle of leaf) Marmande VR) 5. Inflorescence inflorescence type (2^(nd) and 3^(rd) truss) mainly uniparous intermediate (Dynamo) type (3^(rd) inflorescence) forked (2 major axes) forked average number of flowers in 5 6.1 inflorescence (3^(rd) inflorescence) leafy or “running” inflorescence (3^(rd) occasional occasional inflorescence) 6. Flower calyx normal (lobes awl macrocalyx shaped) calyx-lobes shorter than corolla approx. equaling corolla corolla color yellow yellow style pubescence absent or very scarce absent or very scarce (Campbell 1327) anthers all fused into tube all fused into tube fasciation (1^(st) flower of 2^(nd) or 3^(rd) absent (Monalbo, absent inflorescence) Moneymaker) color yellow yellow (Marmande VR) 7. Fruit typical shape in longitudinal section elliptical elliptical (3^(rd) fruit of 2^(nd) or 3^(rd) cluster) shape of transverse/cross section (3^(rd) angular angular fruit of 2^(nd) or 3^(rd) cluster) shape of stem end (3^(rd) fruit of 2^(nd) or 3^(rd) indented indented cluster) shape of blossom end (3^(rd) fruit of 2^(nd) or flat to pointed/ flat to pointed/ 3^(rd) cluster) nippled (Cal J, Early nippled Mech, Peto Gro) size of blossom scar very small (Cerise, small Early Mech, Europeel, Heinz 1706, Peto Gro, Rio Grande) shape of pistil scar (3^(rd) fruit of 2^(nd) or dot dot 3^(rd) cluster) peduncle: abscission layer (3^(rd) fruit of absent (jointless) absent 2^(nd) or 3^(rd) cluster) (Aledo, Bandera, Count, Lerica) ribbing at peduncle end weak (Early Mech, absent or very weak Hypeel 244, Melody, Peto Gro, Rio Grande) depression at peduncle end weak (Futuria, weak Melody) size of stem/peduncle scar medium medium (Montfavet H 63.4, Montfavet H 63.5, Rutgers) point of detachment of fruit at harvest at calyx attachment at calyx attachment (3^(rd) fruit of 2^(nd) or 3^(rd) cluster) length of mature fruit (stem axis; 3^(rd) 58.1 mm 57.6 mm fruit of 2^(nd) or 3^(rd) cluster) diameter of fruit at widest point (3^(rd) 50.6 mm 45.7 mm fruit of 2^(nd) or 3^(rd) cluster) weight of mature fruit (3^(rd) fruit of 2^(nd) 89 grams 70.2 grams or 3^(rd) cluster) size medium (Alphamech, medium Diego) ratio length/diameter medium (Early Mech, medium Peto Gro) core coreless (absent or coreless smaller than 6 × 6 mm) number of locules 2 or 3 (Alphamech, 2 or 3 Futuria) surface slightly rough smooth base color (mature-green stage) apple or medium apple or medium green (Heinz green 1439 VF) pattern (mature-green stage) uniform green uniform green green shoulder (before maturity) absent (Felicia, Rio absent Grande, Trust) intensity of green color of fruit (before medium (Rody) medium maturity) color at maturity (full-ripe) red (Ferline, Daniela, red Montfavet H 63.5) color of flesh at maturity (full-ripe) red/crimson red crimson (Ferline, Saint-Pierre) flesh color uniform uniform locular gel color of table-ripe fruit red red firmness firm (Fernova, firm Konsul, Tradiro) shelf life medium (Durinta) long time of flowering medium late (Montfavet H 63.5, Prisca) time of maturity late (Manific, Saint- late Pierre) ripening (blossom-to-stem axis) uniform uniform ripening (peripheral to central radial uniformity uniformity axis) epidermis color yellow yellow epidermis normal normal epidermis texture average tender thickness of pericarp medium (Carmello, medium Europeel, Floradade, Heinz 1706, Montfavet H 63.5) dry matter content (at maturity) medium low sensitivity to silvering insensitive insensitive (Marathon, Sano) 8. Chemistry and Composition of Full-Ripe Fruits pH 4.23 4.232 titratable acidity, as % citric 0.539 0.5344 total solids (dry matter, seeds and skin 6.97 7.0608 removed) soluble Solids as °Brix 5.93 5.93 9. Phenology seeding to 50% flow (1 open on 50%  55 days  55 days of plants) seeding to once over harvest (if 130 days 141 days applicable) fruiting season medium (Westover) relative maturity in areas tested late late 10. Adaptation culture field field principle use(s) whole-pack canning, whole-pack canning, concentrated products concentrated products regions to which adaptation has been California: California: demonstrated Sacramento and Sacramento and Upper San Joaquin Upper San Joaquin Valley Valley *These are typical values. Values may vary due to environment. Other values that are substantially equivalent are within the scope of the invention.

C. Breeding Tomato Line PSQ 176-09PW0002

One aspect of the current invention concerns methods for crossing the tomato line PSQ 176-09PW0002 with itself or a second plant and the seeds and plants produced by such methods. These methods can be used for propagation of line PSQ 176-09PW0002, or can be used to produce hybrid tomato seeds and the plants grown therefrom. Hybrid seeds are produced by crossing line PSQ 176-09PW0002 with second tomato parent line.

The development of new varieties using one or more starting varieties is well known in the art. In accordance with the invention, novel varieties may be created by crossing line PSQ 176-09PW0002 followed by multiple generations of breeding according to such well known methods. New varieties may be created by crossing with any second plant. In selecting such a second plant to cross for the purpose of developing novel lines, it may be desired to choose those plants which either themselves exhibit one or more selected desirable characteristics or which exhibit the desired characteristic(s) when in hybrid combination. Once initial crosses have been made, inbreeding and selection take place to produce new varieties. For development of a uniform line, often five or more generations of selfing and selection are involved.

Uniform lines of new varieties may also be developed by way of double-haploids. This technique allows the creation of true breeding lines without the need for multiple generations of selfing and selection. In this manner true breeding lines can be produced in as little as one generation. Haploid embryos may be produced from microspores, pollen, anther cultures, or ovary cultures. The haploid embryos may then be doubled autonomously, or by chemical treatments (e.g. colchicine treatment). Alternatively, haploid embryos may be grown into haploid plants and treated to induce chromosome doubling. In either case, fertile homozygous plants are obtained. In accordance with the invention, any of such techniques may be used in connection with line PSQ 176-09PW0002 and progeny thereof to achieve a homozygous line.

Backcrossing can also be used to improve an inbred plant. Backcrossing transfers a specific desirable trait from one inbred or non-inbred source to an inbred that lacks that trait. This can be accomplished, for example, by first crossing a superior inbred (A) (recurrent parent) to a donor inbred (non-recurrent parent), which carries the appropriate locus or loci for the trait in question. The progeny of this cross are then mated back to the superior recurrent parent (A) followed by selection in the resultant progeny for the desired trait to be transferred from the non-recurrent parent. After five or more backcross generations with selection for the desired trait, the progeny have the characteristic being transferred, but are like the superior parent for most or almost all other loci. The last backcross generation would be selfed to give pure breeding progeny for the trait being transferred.

The line of the present invention is particularly well suited for the development of new lines based on the elite nature of the genetic background of the line. In selecting a second plant to cross with PSQ 176-09PW0002 for the purpose of developing novel tomato lines, it will typically be preferred to choose those plants which either themselves exhibit one or more selected desirable characteristics or which exhibit the desired characteristic(s) when in hybrid combination. Examples of desirable traits may include, in specific embodiments, high seed yield, high seed germination, seedling vigor, high fruit yield, disease tolerance or resistance, and adaptability for soil and climate conditions. Consumer-driven traits, such as a fruit shape, color, texture, and taste are other examples of traits that may be incorporated into new lines of tomato plants developed by this invention.

D. Performance Characteristics

Performance characteristics of the line PSQ 176-09PW0002 were the subject of an objective analysis of the performance traits of the line relative to other lines. The results of the analysis are presented below.

TABLE 2 Performance characteristics of PSQ 176-09PW0002 and Comparative Variety PSQ 176-LAW Characteristic PSQ 176-09PW0002 PSQ-176-LAW Nematode Resistance present absent

E. Further Embodiments of the Invention

In certain aspects, the invention provides plants modified to include at least a first desired heritable trait. Such plants may, in one embodiment, be developed by a plant breeding technique called backcrossing, wherein essentially all of the morphological and physiological characteristics of a variety are recovered in addition to a genetic locus transferred into the plant via the backcrossing technique. The term single locus converted plant as used herein refers to those tomato plants which are developed by a plant breeding technique called backcrossing, wherein essentially all of the morphological and physiological characteristics of a variety are recovered in addition to the single locus transferred into the variety via the backcrossing technique. By essentially all of the morphological and physiological characteristics, it is meant that the characteristics of a plant are recovered that are otherwise present when compared in the same environment, other than an occasional variant trait that might arise during backcrossing or direct introduction of a transgene.

Backcrossing methods can be used with the present invention to improve or introduce a characteristic into the present variety. The parental tomato plant which contributes the locus for the desired characteristic is termed the nonrecurrent or donor parent. This terminology refers to the fact that the nonrecurrent parent is used one time in the backcross protocol and therefore does not recur. The parental tomato plant to which the locus or loci from the nonrecurrent parent are transferred is known as the recurrent parent as it is used for several rounds in the backcrossing protocol.

In a typical backcross protocol, the original variety of interest (recurrent parent) is crossed to a second variety (nonrecurrent parent) that carries the single locus of interest to be transferred. The resulting progeny from this cross are then crossed again to the recurrent parent and the process is repeated until a tomato plant is obtained wherein essentially all of the morphological and physiological characteristics of the recurrent parent are recovered in the converted plant, in addition to the single transferred locus from the nonrecurrent parent.

The selection of a suitable recurrent parent is an important step for a successful backcrossing procedure. The goal of a backcross protocol is to alter or substitute a single trait or characteristic in the original variety. To accomplish this, a single locus of the recurrent variety is modified or substituted with the desired locus from the nonrecurrent parent, while retaining essentially all of the rest of the desired genetic, and therefore the desired physiological and morphological constitution of the original variety. The choice of the particular nonrecurrent parent will depend on the purpose of the backcross; one of the major purposes is to add some commercially desirable trait to the plant. The exact backcrossing protocol will depend on the characteristic or trait being altered and the genetic distance between the recurrent and nonrecurrent parents. Although backcrossing methods are simplified when the characteristic being transferred is a dominant allele, a recessive allele, or an additive allele (between recessive and dominant), may also be transferred. In this instance it may be necessary to introduce a test of the progeny to determine if the desired characteristic has been successfully transferred.

In one embodiment, progeny tomato plants of a backcross in which PSQ 176-09PW0002 is the recurrent parent comprise (i) the desired trait from the non-recurrent parent and (ii) all of the physiological and morphological characteristics of tomato line PSQ 176-09PW0002 as determined at the 5% significance level when grown in the same environmental conditions.

Tomato varieties can also be developed from more than two parents. The technique, known as modified backcrossing, uses different recurrent parents during the backcrossing. Modified backcrossing may be used to replace the original recurrent parent with a variety having certain more desirable characteristics or multiple parents may be used to obtain different desirable characteristics from each.

Many single locus traits have been identified that are not regularly selected for in the development of a new inbred but that can be improved by backcrossing techniques. Single locus traits may or may not be transgenic; examples of these traits include, but are not limited to, herbicide resistance, resistance to bacterial, fungal, or viral disease, insect resistance, modified fatty acid or carbohydrate metabolism, and altered nutritional quality. These comprise genes generally inherited through the nucleus.

Direct selection may be applied where the single locus acts as a dominant trait. For this selection process, the progeny of the initial cross are assayed for viral resistance and/or the presence of the corresponding gene prior to the backcrossing. Selection eliminates any plants that do not have the desired gene and resistance trait, and only those plants that have the trait are used in the subsequent backcross. This process is then repeated for all additional backcross generations.

Selection of tomato plants for breeding is not necessarily dependent on the phenotype of a plant and instead can be based on genetic investigations. For example, one can utilize a suitable genetic marker which is closely genetically linked to a trait of interest. One of these markers can be used to identify the presence or absence of a trait in the offspring of a particular cross, and can be used in selection of progeny for continued breeding. This technique is commonly referred to as marker assisted selection. Any other type of genetic marker or other assay which is able to identify the relative presence or absence of a trait of interest in a plant can also be useful for breeding purposes. Procedures for marker assisted selection are well known in the art. Such methods will be of particular utility in the case of recessive traits and variable phenotypes, or where conventional assays may be more expensive, time consuming or otherwise disadvantageous. Types of genetic markers which could be used in accordance with the invention include, but are not necessarily limited to, Simple Sequence Length Polymorphisms (SSLPs) (Williams et al., Nucleic Acids Res., 1 8:6531 6535, 1990), Randomly Amplified Polymorphic DNAs (RAPDs), DNA Amplification Fingerprinting (DAF), Sequence Characterized Amplified Regions (SCARs), Arbitrary Primed Polymerase Chain Reaction (AP-PCR), Amplified Fragment Length Polymorphisms (AFLPs) (EP 534 858, specifically incorporated herein by reference in its entirety), and Single Nucleotide Polymorphisms (SNPs) (Wang et al., Science, 280:1077-1082, 1998).

F. Plants Derived from Tomato Line PSQ 176-09PW0002 by Genetic Engineering

Many useful traits that can be introduced by backcrossing, as well as directly into a plant, are those which are introduced by genetic transformation techniques. Genetic transformation may therefore be used to insert a selected transgene into the tomato line of the invention or may, alternatively, be used for the preparation of transgenes which can be introduced by backcrossing. Methods for the transformation of plants that are well known to those of skill in the art and applicable to many crop species include, but are not limited to, electroporation, microprojectile bombardment, Agrobacterium-mediated transformation and direct DNA uptake by protoplasts.

To effect transformation by electroporation, one may employ either friable tissues, such as a suspension culture of cells or embryogenic callus or alternatively one may transform immature embryos or other organized tissue directly. In this technique, one would partially degrade the cell walls of the chosen cells by exposing them to pectin-degrading enzymes (pectolyases) or mechanically wound tissues in a controlled manner.

An efficient method for delivering transforming DNA segments to plant cells is microprojectile bombardment. In this method, particles are coated with nucleic acids and delivered into cells by a propelling force. Exemplary particles include those comprised of tungsten, platinum, and preferably, gold. For the bombardment, cells in suspension are concentrated on filters or solid culture medium. Alternatively, immature embryos or other target cells may be arranged on solid culture medium. The cells to be bombarded are positioned at an appropriate distance below the macroprojectile stopping plate.

Microprojectile bombardment techniques are widely applicable, and may be used to transform virtually any plant species. An illustrative embodiment of a method for delivering DNA into plant cells by acceleration is the Biolistics Particle Delivery System, which can be used to propel particles coated with DNA or cells through a screen, such as a stainless steel or Nytex screen, onto a surface covered with target cells. The screen disperses the particles so that they are not delivered to the recipient cells in large aggregates.

Agrobacterium-mediated transfer is another widely applicable system for introducing gene loci into plant cells. An advantage of the technique is that DNA can be introduced into whole plant tissues, thereby bypassing the need for regeneration of an intact plant from a protoplast. Modern Agrobacterium transformation vectors are capable of replication in E. coli as well as Agrobacterium, allowing for convenient manipulations (Klee et al., Bio-Technology, 3(7):637-642, 1985). Moreover, recent technological advances in vectors for Agrobacterium-mediated gene transfer have improved the arrangement of genes and restriction sites in the vectors to facilitate the construction of vectors capable of expressing various polypeptide coding genes. The vectors described have convenient multi-linker regions flanked by a promoter and a polyadenylation site for direct expression of inserted polypeptide coding genes. Additionally, Agrobacterium containing both armed and disarmed Ti genes can be used for transformation.

In those plant strains where Agrobacterium-mediated transformation is efficient, it is the method of choice because of the facile and defined nature of the gene locus transfer. The use of Agrobacterium-mediated plant integrating vectors to introduce DNA into plant cells is well known in the art (Fraley et al., Bio/Technology, 3:629-635, 1985; U.S. Pat. No. 5,563,055).

Transformation of plant protoplasts also can be achieved using methods based on calcium phosphate precipitation, polyethylene glycol treatment, electroporation, and combinations of these treatments (see, e.g., Potrykus et al., Mol. Gen. Genet., 199:183-188, 1985; Omirulleh et al., Plant Mol. Biol., 21(3):415-428, 1993; Fromm et al., Nature, 312:791-793, 1986; Uchimiya et al., Mol. Gen. Genet., 204:204, 1986; Marcotte et al., Nature, 335:454, 1988). Transformation of plants and expression of foreign genetic elements is exemplified in Choi et al. (Plant Cell Rep., 13: 344-348, 1994), and Ellul et al. (Theor. Appl. Genet., 107:462-469, 2003).

A number of promoters have utility for plant gene expression for any gene of interest including but not limited to selectable markers, scoreable markers, genes for pest tolerance, disease resistance, nutritional enhancements and any other gene of agronomic interest. Examples of constitutive promoters useful for plant gene expression include, but are not limited to, the cauliflower mosaic virus (CaMV) P-35S promoter, which confers constitutive, high-level expression in most plant tissues (see, e.g., Odel et al., Nature, 313:810, 1985), including in monocots (see, e.g., Dekeyser et al., Plant Cell, 2:591, 1990; Terada and Shimamoto, Mol. Gen. Genet., 220:389, 1990); a tandemly duplicated version of the CaMV 35S promoter, the enhanced 35S promoter (P-e35S) the nopaline synthase promoter (An et al., Plant Physiol., 88:547, 1988), the octopine synthase promoter (Fromm et al., Plant Cell, 1:977, 1989); and the figwort mosaic virus (P-FMV) promoter as described in U.S. Pat. No. 5,378,619 and an enhanced version of the FMV promoter (P-eFMV) where the promoter sequence of P-FMV is duplicated in tandem, the cauliflower mosaic virus 19S promoter, a sugarcane bacilliform virus promoter, a commelina yellow mottle virus promoter, and other plant DNA virus promoters known to express in plant cells.

A variety of plant gene promoters that are regulated in response to environmental, hormonal, chemical, and/or developmental signals can also be used for expression of an operably linked gene in plant cells, including promoters regulated by (1) heat (Callis et al., Plant Physiol., 88:965, 1988), (2) light (e.g., pea rbcS-3A promoter, Kuhlemeier et al., Plant Cell, 1:471, 1989; maize rbcS promoter, Schaffner and Sheen, Plant Cell, 3:997, 1991; or chlorophyll a/b-binding protein promoter, Simpson et al., EMBO J., 4:2723, 1985), (3) hormones, such as abscisic acid (Marcotte et al., Plant Cell, 1:969, 1989), (4) wounding (e.g., wunl, Siebertz et al., Plant Cell, 1:961, 1989); or (5) chemicals such as methyl jasmonate, salicylic acid, or Safener. It may also be advantageous to employ organ-specific promoters (e.g., Roshal et al., EMBO J., 6:1155, 1987; Schernthaner et al., EMBO J., 7:1249, 1988; Bustos et al., Plant Cell, 1:839, 1989).

Exemplary nucleic acids which may be introduced to plants of this invention include, for example, DNA sequences or genes from another species, or even genes or sequences which originate with or are present in the same species, but are incorporated into recipient cells by genetic engineering methods rather than classical reproduction or breeding techniques. However, the term “exogenous” is also intended to refer to genes that are not normally present in the cell being transformed, or perhaps simply not present in the form, structure, etc., as found in the transforming DNA segment or gene, or genes which are normally present and that one desires to express in a manner that differs from the natural expression pattern, e.g., to over-express. Thus, the term “exogenous” gene or DNA is intended to refer to any gene or DNA segment that is introduced into a recipient cell, regardless of whether a similar gene may already be present in such a cell. The type of DNA included in the exogenous DNA can include DNA which is already present in the plant cell, DNA from another plant, DNA from a different organism, or a DNA generated externally, such as a DNA sequence containing an antisense message of a gene, or a DNA sequence encoding a synthetic or modified version of a gene.

Many hundreds if not thousands of different genes are known and could potentially be introduced into a tomato plant according to the invention. Non-limiting examples of particular genes and corresponding phenotypes one may choose to introduce into a tomato plant include one or more genes for insect tolerance, such as a Bacillus thuringiensis (B.t.) gene, pest tolerance such as genes for fungal disease control, herbicide tolerance such as genes conferring glyphosate tolerance, and genes for quality improvements such as yield, nutritional enhancements, environmental or stress tolerances, or any desirable changes in plant physiology, growth, development, morphology or plant product(s). For example, structural genes would include any gene that confers insect tolerance including but not limited to a Bacillus insect control protein gene as described in WO 99/31248, herein incorporated by reference in its entirety, U.S. Pat. No. 5,689,052, herein incorporated by reference in its entirety, U.S. Pat. Nos. 5,500,365 and 5,880,275, herein incorporated by reference in their entirety. In another embodiment, the structural gene can confer tolerance to the herbicide glyphosate as conferred by genes including, but not limited to Agrobacterium strain CP4 glyphosate resistant EPSPS gene (aroA:CP4) as described in U.S. Pat. No. 5,633,435, herein incorporated by reference in its entirety, or glyphosate oxidoreductase gene (GOX) as described in U.S. Pat. No. 5,463,175, herein incorporated by reference in its entirety.

Alternatively, the DNA coding sequences can affect these phenotypes by encoding a non-translatable RNA molecule that causes the targeted inhibition of expression of an endogenous gene, for example via antisense- or cosuppression-mediated mechanisms (see, for example, Bird et al., Biotech. Gen. Engin. Rev., 9:207, 1991). The RNA could also be a catalytic RNA molecule (i.e., a ribozyme) engineered to cleave a desired endogenous mRNA product (see for example, Gibson and Shillito, Mol. Biotech., 7:125,1997). Thus, any gene which produces a protein or mRNA which expresses a phenotype or morphology change of interest is useful for the practice of the present invention.

G. Definitions

In the description and tables herein, a number of terms are used. In order to provide a clear and consistent understanding of the specification and claims, the following definitions are provided:

Allele: Any of one or more alternative forms of a gene locus, all of which alleles relate to one trait or characteristic. In a diploid cell or organism, the two alleles of a given gene occupy corresponding loci on a pair of homologous chromosomes.

Backcrossing: A process in which a breeder repeatedly crosses hybrid progeny, for example a first generation hybrid (F₁), back to one of the parents of the hybrid progeny. Backcrossing can be used to introduce one or more single locus conversions from one genetic background into another.

Crossing: The mating of two parent plants.

Cross-pollination: Fertilization by the union of two gametes from different plants.

Diploid: A cell or organism having two sets of chromosomes.

Emasculate: The removal of plant male sex organs or the inactivation of the organs with a cytoplasmic or nuclear genetic factor or a chemical agent conferring male sterility.

Enzymes: Molecules which can act as catalysts in biological reactions.

F₁ Hybrid: The first generation progeny of the cross of two nonisogenic plants.

Genotype: The genetic constitution of a cell or organism.

Haploid: A cell or organism having one set of the two sets of chromosomes in a diploid.

Linkage: A phenomenon wherein alleles on the same chromosome tend to segregate together more often than expected by chance if their transmission was independent.

Marker: A readily detectable phenotype, preferably inherited in codominant fashion (both alleles at a locus in a diploid heterozygote are readily detectable), with no environmental variance component, i.e., heritability of 1.

Phenotype: The detectable characteristics of a cell or organism, which characteristics are the manifestation of gene expression.

Quantitative Trait Loci (QTL): Quantitative trait loci (QTL) refer to genetic loci that control to some degree numerically representable traits that are usually continuously distributed.

Resistance: As used herein, the terms “resistance” and “tolerance” are used interchangeably to describe plants that show no symptoms to a specified biotic pest, pathogen, abiotic influence or environmental condition. These terms are also used to describe plants showing some symptoms but that are still able to produce marketable product with an acceptable yield. Some plants that are referred to as resistant or tolerant are only so in the sense that they may still produce a crop, even though the plants are stunted and the yield is reduced.

Regeneration: The development of a plant from tissue culture.

Royal Horticultural Society (RHS) color chart value: The RHS color chart is a standardized reference which allows accurate identification of any color. A color's designation on the chart describes its hue, brightness and saturation. A color is precisely named by the RHS color chart by identifying the group name, sheet number and letter, e.g., Yellow-Orange Group 19A or Red Group 41B.

Self-pollination: The transfer of pollen from the anther to the stigma of the same plant.

Single Locus Converted (Conversion) Plant: Plants which are developed by a plant breeding technique called backcrossing wherein essentially all of the morphological and physiological characteristics of an inbred are recovered in addition to the characteristics conferred by the single locus transferred into the inbred via the backcrossing technique. By “essentially all,” it is meant that all of the characteristics of a plant are recovered that are otherwise present when compared in the same environment and save for the converted locus, other than an occasional variant trait that might arise during backcrossing or direct introduction of a transgene. A single locus may comprise one gene, or in the case of transgenic plants, one or more transgenes integrated into the host genome at a single site (locus).

Substantially Equivalent: A characteristic that, when compared, does not show a statistically significant difference (e.g., p=0.05) from the mean.

Tissue Culture: A composition comprising isolated cells of the same or a different type or a collection of such cells organized into parts of a plant.

Transgene: A genetic locus comprising a sequence which has been introduced into the genome of a tomato plant by transformation.

H. Deposit Information

A deposit of tomato line PSQ 176-09PW0002, disclosed above and recited in the claims, has been made with the American Type Culture Collection (ATCC), 10801 University Blvd., Manassas, Va. 20110-2209. The date of deposit was Nov. 18, 2011. The accession number for those deposited seeds of tomato line PSQ 176-09PW0002 is ATCC Accession No. PTA-12267. Upon issuance of a patent, all restrictions upon the deposit will be removed, and the deposit is intended to meet all of the requirements of 37 C.F.R. §1.801-1.809. The deposit will be maintained in the depository for a period of 30 years, or 5 years after the last request, or for the effective life of the patent, whichever is longer, and will be replaced if necessary during that period.

Although the foregoing invention has been described in some detail by way of illustration and example for purposes of clarity and understanding, it will be obvious that certain changes and modifications may be practiced within the scope of the invention, as limited only by the scope of the appended claims.

All references cited herein are hereby expressly incorporated herein by reference. 

1. A seed of tomato line PSQ 176-09PW0002, a sample of seed of said line having been deposited under ATCC Accession Number PTA-12267.
 2. A plant of tomato line PSQ 176-09PW0002, a sample of seed of said line having been deposited under ATCC Accession Number PTA-12267.
 3. A plant part of the plant of claim
 2. 4. The plant part of claim 3, wherein said part is selected from the group consisting of a leaf, an ovule, pollen, a fruit, or a cell.
 5. A tomato plant, or a part thereof, having all the physiological and morphological characteristics of the tomato plant of claim
 2. 6. A tissue culture of regenerable cells of tomato line PSQ 176-09PW0002, a sample of seed of said line having been deposited under ATCC Accession Number PTA-12267.
 7. The tissue culture according to claim 6, comprising cells or protoplasts from a plant part selected from the group consisting of embryos, meristems, cotyledons, pollen, leaves, anthers, roots, root tips, pistil, flower, seed and stalks.
 8. A tomato plant regenerated from the tissue culture of claim 6, wherein the regenerated plant expresses all of the physiological and morphological characteristics of tomato line PSQ 176-09PW0002, a sample of seed of said line having been deposited under ATCC Accession Number PTA-12267.
 9. A method of producing seed, comprising crossing the plant of claim 2 with itself or a second plant, thereby producing a seed.
 10. The method of claim 9, wherein the plant of tomato line PSQ 176-09PW0002 is the female parent.
 11. The method of claim 9, wherein the plant of tomato line PSQ 176-09PW0002 is the male parent.
 12. An F1 hybrid seed produced by the method of claim
 9. 13. An F1 hybrid plant produced by growing the seed of claim
 12. 14. A method for producing a seed of a line PSQ 176-09PW0002-derived tomato plant comprising the steps of: (a) crossing a tomato plant of line PSQ 176-09PW0002 with a second tomato plant, a sample of seed of said line having been deposited under ATCC Accession Number PTA-12267; and (b) allowing seed of a PSQ 176-09PW0002-derived tomato plant to form.
 15. The method of claim 14, further comprising the steps of: (c) crossing a plant grown from said PSQ 176-09PW0002-derived tomato seed with itself or a second tomato plant to yield additional PSQ 176-09PW0002-derived tomato seed; (d) growing said additional PSQ 176-09PW0002-derived tomato seed of step (c) to yield additional PSQ 176-09PW0002-derived tomato plants; and (e) repeating the crossing and growing steps of (c) and (d) to generate further PSQ 176-09PW0002-derived tomato plants.
 16. A method of vegetatively propagating a plant of tomato line PSQ 176-09PW0002 comprising the steps of: (a) collecting tissue capable of being propagated from a plant of tomato line PSQ 176-09PW0002, a sample of seed of said line having been deposited under ATCC Accession Number PTA-12267; (b) cultivating said tissue to obtain proliferated shoots; and (c) rooting said proliferated shoots to obtain rooted plantlets.
 17. The method of claim 16, further comprising growing plants from said rooted plantlets.
 18. A method of introducing a desired trait into tomato line PSQ 176-09PW0002 comprising: (a) crossing a plant of line PSQ 176-09PW0002 with a second tomato plant that comprises a desired trait to produce F1 progeny, a sample of seed of said line PSQ 176-09PW0002 having been deposited under ATCC Accession Number PTA-12267; (b) selecting an F1 progeny that comprises the desired trait; (c) crossing the selected F1 progeny with a plant of line PSQ 176-09PW0002 to produce backcross progeny; (d) selecting backcross progeny comprising the desired trait and the physiological and morphological characteristic of tomato line PSQ 176-09PW0002; and (e) repeating steps (c) and (d) three or more times to produce selected fourth or higher backcross progeny that comprise the desired trait and essentially all of the physiological and morphological characteristics of tomato line PSQ 176-09PW0002 when grown in the same environmental conditions.
 19. A tomato plant produced by the method of claim
 18. 20. A seed that produces the plant of claim
 19. 21. A method of producing a plant of tomato line PSQ 176-09PW0002 comprising an added desired trait, the method comprising introducing a transgene conferring the desired trait into a plant of tomato line PSQ 176-09PW0002, a sample of seed of said line PSQ 176-09PW0002 having been deposited under ATCC Accession Number PTA-12267.
 22. A tomato plant produced by the method of claim
 21. 23. A seed that produces the plant of claim
 22. 24. A method of producing tomatoes comprising: (a) obtaining the plant of claim 2, wherein the plant has been cultivated to maturity, and (b) collecting tomatoes from the plant. 